Lets see your O.B. speakers....!

opnly bafld · « **Reply #580 on:** 4 Jul 2024, 12:09 am »

Just finished building these open baffle speakers.
Wild Burro Betsy and GRS 12" subwoofer, a single ended tube amplifier for the wideband drivers and a pair of ~~Dayton Audio SPA250 plate amplifiers~~ 12mH inductors and a push/pull tube amplifier for the bass drivers.

12/3/24 Edit: a couple of weeks ago I decided to try some inductors that had been collecting dust for a few years and liked the result so much the Dayton plate amplifiers are now collecting dust (again).

jk@home · « **Reply #581 on:** 4 Jul 2024, 11:55 am »

Nice, I guess you would call that a WAW (woofer assisted wideband)? Question; looking at the plate amp you are using, on the PE site it appears to be in an enclosure (with loose wires in the back)? How do you have it wired into the FR?

opnly bafld · « **Reply #582 on:** 4 Jul 2024, 12:45 pm »

Quote from: jk@home on 4 Jul 2024, 11:55 am

Nice, I guess you would call that a WAW (woofer assisted wideband)? Question; looking at the plate amp you are using, on the PE site it appears to be in an enclosure (with loose wires in the back)? How do you have it wired into the FR?

Thanks!

I prefer "Fast" fullrange assisted.

2 pairs of speaker wire out of the tube amplifier - 1 pair to the Betsy (upper bi-amp input terminal) - 1 pair to the plate amp input - plate amp output wired to lower connections on the bi-amp input terminal.

https://www.parts-express.com/Gold-Plated-Bi-Amp-Terminal-260-304?quantity=1

jk@home · « **Reply #583 on:** 4 Jul 2024, 07:26 pm »

Thanks, that sounds like a simple hookup. Think I will go the same route. I'm using mono amps at the speakers, so the extra wiring for the bass amps/drivers will be minimum.

dcbingaman · « **Reply #584 on:** 10 Jul 2024, 01:06 am »

The VPE Electrodynamics Crystal Dipole 2's. Uses the Cube Audio F10 Select in a 1/2" thick acrylic open baffle 16" x 48" on Magna Riser stands. Augmented in the bass by twin VPE Electrodynamics Model 1 Little Dipole Woofers DSP. Sounds Awesome !

Driver EQed using Schiit Audio Lokius box. Schiit Audio Kara Preamp and Dynamo / Radial Stereo 70 Series III EL34 Tube Power Amp

ahola1968 · « **Reply #585 on:** 14 Jul 2024, 07:33 pm »

ahola1968 · « **Reply #586 on:** 14 Jul 2024, 07:36 pm »

New 3-way OB conception with Electro Voice ST350B

Poultrygeist · « **Reply #587 on:** 15 Jul 2024, 10:25 am »

8" Zenith alnico drivers over 10" bass woofers from PE. The Zeniths were pulled from a 1957 console and look and perform like larger versions of Coral Holey Baskets. The make and model numbers were mysteriously blacked out.

Poultrygeist · « **Reply #588 on:** 15 Jul 2024, 10:59 am »

The 8" Zeniths next to the Lii Audio F-15s over 15" Eminence Alphas. The F-15's are the heaviest wide band drivers I've used and Steve of Decware fame claims their sound is reminiscent of the big alnico drivers of yesteryear. I think my 12" Zenith 49CZ803's from the 1950's on the opposite side of the room have the sweeter tone.

Poultrygeist · « **Reply #589 on:** 5 Aug 2024, 04:05 pm »

After spending more time with the last version of the 8" Zeniths ( see above ), I felt the 10" bass woofers were lacking so I replaced them with a pair of 16" woofers and the bass drastically improved. These woofers were harvested from a pair of Sansui kabuki's left on the curb. Have no idea of their specs but they sound great in OB.

Poultrygeist · « **Reply #590 on:** 5 Aug 2024, 04:22 pm »

I run the 8" Zeniths full range from their own amp. The bass woofers have a separate amp and are low passed with a 70hz filter. I used foam hockey pucks between the lower baffle and upper baffle supports.

Poultrygeist · « **Reply #591 on:** 5 Aug 2024, 08:13 pm »

After trying several amps ( Volt+D and Fosi Za3 ) I went with an APPJ/Miniwatt S-1 to drive the very efficient Zenith alnico's. The Sansui bass woofers are powered by a stereo Denon DRA-335R. With its bass/treble and variable loudness controls I was able to dial in the bass to my satisfaction. A passive preamp with two pair of outputs sends the signal from a Panasonic CD/DVD F87's to both amps. Comparing the two class D amps I found the Volt+D to be somewhat more resolving that the Fosi. But the Zeniths sounded as though they were designed for a flea watt tube amp and in actuality they were as that was all that was available back in 1957.

Since I took this picture I added a Khadas Tone Board DAC to the CD changer's digital output and it made a nice improvement in SQ.

jk@home · « **Reply #592 on:** 6 Aug 2024, 01:43 am »

I bought a couple of those Fosi Za3 amps (using one channel each) to drive a pair of ESS Heil AMTs that I will be using on the OB I'm building. Thought I had saved money with those...then found out about op-amp swapping.

ebag4 · « **Reply #593 on:** 6 Aug 2024, 09:05 pm »

I completed a rebuild of my son’s V1s last month:

What they were:

What they are today:

And what was left of the original:

Best,
Ed

kd4ylq · « **Reply #594 on:** 7 Aug 2024, 03:27 pm »

Impressive woodworking ED! - nice job visually and I'll bet they sound great too!

Jim KD4YLQ

Poultrygeist · « **Reply #595 on:** 11 Aug 2024, 11:02 am »

For many folks passive crossovers are viewed as a necessity but if you're using a SET amp they can literally ruin the magic. Most of us use full range drivers in open baffles which by definition are designed to run full range. The other choice can be a sad attempt to stitch two dissimilar drivers together with a passive network and hope for the best. My electronic crossovers and DSP's are in storage and I need to sell them as they all impart their own sonic signature to the system. They can work ok for less critical bass woofers driven by solid state amps but never again will I use them with a SET amp. Here I'm using a 70hz low pass filter on the bass driven by their own SS amp with nothing between the single ended tube amp and vintage alnico drivers. The result is one of the simplest and best sounding OB's I've experienced. Those old 8" Zenith alnico's from 1957 are a real treasure and they put my Lowthers to shame.

planet10 · « **Reply #596 on:** 11 Aug 2024, 07:42 pm »

Nice looking Coral mid/top

dave

Poultrygeist · « **Reply #597 on:** 11 Aug 2024, 10:53 pm »

Thanks Dave

pompon · « **Reply #598 on:** 22 Aug 2024, 04:40 pm »

Maybe an improved version of the big ones on the sides.

The advantage is at the soundstage where the sound coming from the wall is not partially blocked by the size of the baffle.
I can put the baffle closer to me and the music dont move toward me but the soundstage depth is greatly better.
The stage height is about the same as my big one where the mid range is at the ear level.
The 18 inch are connected from the baffle on the side to have full body.
My plan is do a L where the baffle width will be just enough to fit the speaker and the long part of the "L" will be the 18inch firing toward the center or the side ...
"L" frame is inspired with gr research recommandation.

Baffle are at 66inch from the wall and I am at 70 inch from the baffle. It's just WOW.

wgraft5 · « **Reply #599 on:** 27 Aug 2024, 03:57 pm »

Rebuild vesion 3.1, Modified ABX/LaDolce Audio OB Baffles.

I wanted to try out the round port in lieu of the rectangle. I like the way the round port looks and it works and sounds better than before.

These do all the audiophile things very well, resolving, the sound stage is deep, wide, and tall. Its allmost like I have suround sound now?!
I have been searching for the low bass sound, kinda like car stereo's. Now I have that sound and I am not running my subwoofer. I had to use the input cable for my other amp. So I am now bi-amping. I have the Mono Extreams on the 15" and Tweeter and the 18"
gets its own amp. Its the chi-fi fun-fi Aiyma A07 with Sparkos 3602 op-amps. Sounds good for now will be upgraded at some point.

Thanks for lookin'
Wayne in Oregon